The role of cell surface RNAs in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors worldwide. The composition of the tumor cell surface critically regulates cellular interactions with the microenvironment, influencing tumor initiation and progression. While the existence of cell surface RNA has been recently explored in other contexts, its presence on liver cancer cells and its specific impact on HCC progression are unknown. We used a copper-free click chemistry reaction and flow cytometry to detect the presence of RNA on the cell surface of HCC cells. Through functional assays, proteomics, and metabolomics, we analyzed the role of cell surface RNA in HCC. Our research is the first to confirm the existence of cell surface RNA, including glycoRNA (small RNAs modified with N-glycans), on liver cancer cells. We found that SERBP1 plays a crucial role in modulating the expression of cell surface RNAs, including their glycoRNA, which was validated through proteomics and siRNA interference. Our findings suggest that cell surface RNA may promote tumor progression by affecting apoptosis, ribosome function, and taurine metabolism in liver cancer cells. This study provides a new perspective on the surface structure of liver cancer cells and identifies a novel mechanism that may contribute to tumor progression.